At the end of 2009, nearly 45 percent of the county’s residents spoke a language other than English at home, according to county officials. Whites now make up only 45 percent of the population; this county is teeming with Hispanics, as well as Vietnamese, Korean and Chinese families. Its percentage of foreign-born residents jumped to 30 percent in 2008 from 6 percent in 1970, and visits to some of its corners can feel like a trip to a foreign land.

The demographic changes that have swept the county reflect what is happening across the state and much of the nation. It has happened slowly but surely over the course of a generation, becoming increasingly apparent not only in a drive through the 34 cities that fill this sprawling 789-square-mile county south of Los Angeles, but also, most recently, in the results of a presidential election. In 2008, Barack Obama drew 48 percent of the vote here against Senator John McCain of Arizona. (By comparison, in 1980, Jimmy Carter received just 23 percent against Ronald Reagan, the conservative hero whose election as California governor in 1966 and 1970 was boosted in no small part by the affection for him here.)

Two things here really dovetail with the things we've been discussing. One is that this is a clear-cut indicator of one of the major sources of social anxiety for the white, middle-class, 50-and-over folks who are moving into the Tea Party movement. But the numbers also suggest that -- whatever hay the political right may be able to make in the 2010 elections -- in the long run that Tea Party movement may be doomed, unless the GOP shifts gears quickly and comes up with some kind of appeal to younger people and at least some non-whites.

Programming note: I'm going to be appearing as a guest in the 10 o' clock hour on WHHY's "Radio Times" (90.9 FM in Philadelphia) to talk about both the book and this weekend's Beck rally. So among other things, you'll have a chance to call up and harass me verbally for a change.